Soft-formation core drill



April 17, 1928.

5 1,666,726 L. H. WELLENS'IEK SOFT FORMATION CORE .DRILL Filed Aug. 2.1926 llllllll v [Il:

q Fig! Patented Apr. 17, 192.8. Y UNITED STATES PATENT OFFICE.

LOUIS IH. 'WELLENSIEK, OF HOUSTON, TEXAS, ASSIGNOR TO HUGHES TOOLCOMPANY,

i OF HOUSTON, TEXAS, A CORPORATION OF TEXAS.

SOFT-FORMATION CORE DRILL.

Application filed August 2, 1926. Serial No. 126,471.

My invention relates to core drills for cutting soft formationencountered in well drilling.-

It is an object of the invention to construct a core drill adapted tocutthe softer grades of material in well drilling, which drill will bebalanced in its construction and hence will be enabled to operatesmoothly and evenly.

It is also desired to discharge the flushing fluid directly in frontof,each cutting element and in the direction of inclination of thecutter.

It is a further object to form a detachable core catcher seat which willassist in maintaining the core from contact with the Wash of theflushing fluid.

i Referring to the drawing herewith, Fig.

1 is a side view partly in elevation and part- 2.0

3 is a side View, partly in section, of the core catcher seat, removed.Like numerals of reference are applied to like parts in all the views.

In carrying out my invention I provide a ltubular head 1, having anupper threaded socket 2 thereon to receive the drill collar 3, A throughwhich the drill may be lrotated. 3o The lower end of the head isprovided with teeth cut into the wall ofthe head.- These teeth arearranged 'in two sets of three cutters in each set. There is one set ofteeth 4 which are inclined outwardly and one set 5 which are inclinedinwardly.

The manner of forming the teeth is to be noted. They are cut deeplyupward into the wall of the drill, the upper end 6 of the recess betweenadjacent teeth being shown in Fig. 1. The forward side of the adjacenttooth is. cut away at 7 to form a shoulder and below the shoulder theflat forward face 8 of the tooth extends down to a cutting point 9 whichis inclined forwardly.

- The flushing fluid is discharged to the cutters through channels 10issuing through outlets in the shoulders 7 of the teeth and, by notingthe sectioned portion of Fi 1, it will be seen that, when the tooth isdient' to incline it inwardly or outwardly, as the case may be, thewater channels are also bent to provide a discharge of the water alongthe face of the cutter parallel therewith.

The core barrel 11 has a collar 12 secured at its lower end, said'collarbeing threaded preferred manner.

ly in section on the line 1-1 of Fig. 2. Fig. 2 is a bottom plan View ofthe drill. Fig.'

to engage the Vinner threaded wall 13 of the drill.

The core catcher seat 14 is formed of a. thin sleeve of steel the wallsof which are .tapered downwardly except for a short cyis held 'removablyin position lby the lower end of the core barrel collar l2.

The core catching jaws 1G are mounted on a spring collar 17 fitting theseat 14 in any It is to be noted that the seat 14- will enclose thelower end -of the core between the teeth and protect it from the Wash ofthe flushing water.

As will be seen from Fig. 2, the points. of the teeth are bent forwardlyand the edges are also inclined backwardly away from a radial line, tobetter accomplish a shearing' action on thev material andy allow thematerial to be moved away from the cutting pointsv 9. This keeps thecutting points clear of material and mpvcs the cuttings into the path ofthe lushlng fluid.

In operation the rotation of the drill in a 4clockwise direction, asviewed from above,

will force theteeth into the formation `cut ting off portions of thematerial and thestreams of flushing fluid directed-along the faces ofthe cutters will carry the cuttingsupwardly and fiutes or grooves 19 inthe outer side of the head allow passages for the same. The core isprotected fr om being washed by the flushinguid by the vcore catcherand-its seat extending downwardly inside theteeth to the points of thecutting teeth. i

Having thus described the invention what I claim as new and desire to protect by Letters Patent is:`

1. A core drill-including a tubular head, teeth cut deeply into thelower wall thereof,

'each alternate tooth being bent inwardly forminga support, a corecatcher sleeve tapered to fit within the support formed by said teeth,said sleeve extending downwardly to a plane adjacent the cutting edgesof said teeth to close the space between adjacent teeth, means todischarge flushing fluid outside said sleeve, and core engaging means insaid sleeve.

2. 4A core drill including a'tubular head, teeth cut deeply into thelower Wall thereof,

'each alternate tooth being inclined inwardly, aJ core catcher sleevetapered to Ifit the I supports provided by Said inwardly inclined teeth,said sleeve closing the space between said teeth from. a, line abovesaid teeth to a level closely adjacent the lower ends thereof, saidsleeve being also adapted to receive core engaging elements.

In testimony whereof I hereunto affix my l' signature thisQGth day ofJuly D. 1926.

LOUIS H. WELLENSIEK. n

